Such a situation would lead to prolonged power cuts which could lead to an economic downturn, job losses and shut down schools and hospitals, he commented.
He suggested extending coal and nuclear power plants beyond their official closing dates, buying in more electricity from Europe and burning municipal waste in incinerators to generate power.
"All in all it will be a close run thing to provide electricity to keep the lights on through the next decade," he commented.
In response to Prof Fells's statements, Doug Parr, chief scientist for Greenpeace UK described the concentration on older technologies as "naïve".
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